Railway traffic controlling apparatus



Sept 14, 1937. J, M, E A'N 2,092,854

RAILWAY TRAFFIC CONTROLLING APPARATUS Original Filed Jan. 25, 1950-|NVENTORZ M. Pal/Ran Patented Sept. 14, 1937 I UNITED STATES RAILWAYTRAFFIC John M. Pelikan, Grafton, Union Switch & Signal CONTROLLINGArPA- a TUS. r

Pa., assignor to'The Company, Swissvale,

Pa, a corporation of Pennsylvania Application January 25 Renewed May2'7, 1 933 21 Claims.

My invention relates to railway trafiic controlling apparatus, andparticularly to apparatus of the type involving a railway switch and asignal governing trafiic over the switch.

One feature of my invention is the provision of novel and improved meansfor preventing operation of the switch when the signal gives a proceedindication and a train is approaching the signal. y j

I will describe one form of apparatus embodying my invention, and willthen point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form ofapparatus embodying my invention.

Referring to the drawing, the reference characters I and l designate thetrack rails of a stretch of main track A, which rails are divided byinsulated joints 2 to form a main or detector section UV, and anapproach section WY, these sections being separated by an interveningsection YU the purpose of which will be explained hereinafter. Themain-section U-V is provided with a switch B leading into a side trackC. Traffic moving toward the right through the main section UV isgoverned by two signals S and S controlled in part by contacts 8 and 9of the usual home relaysH and H which relays are usually controlled froma distant point such as an interlocking tower or a dispatchers oifice.The control of these relays forms no part of my present invention, and,consequently, the controlling circuits have not been illustrated in thedrawing. The switch B is provided with an operating mechanism or switchmachine D which is also controlled in part from the same remote pointthrough the medium of circuits which are represented in the drawing bythe reference character G.

Each track section UV and W-Y is provided with the usual track circuit,comprising a battery 3 connected across the rails at one end of thesection and a track relay T T respectively, connected across the railsat the other end of the section. An auxiliary relay E and a source ofcurrent 4 are connected in series around one of the insulated joints 2between the main section UV and the intervening section YU, so thatrelay E is normally deenergized, but becomes energized when this jointis bridged by. a train. The intervening section Y-U is so short that nocar can occupy this section without releasing one or both of the trackrelays T T The reference character M designates the usual approachlocking reuay, having a front contact I4 1930, serial'No. 423,347

included.- in the-operating circuits for the switch mechanism D, so thatthe switch B cannot be operated unless this relay is energized. The relay M is provided with a pick-up circuit which passes from terminal X ofa suitable'source of 5 current, through front contact 5 of the.auxiliary relay E, back contact 6 of track relay T and the winding ofrelay M to terminal'O of the same source of current. It follows thatwhen relay M is deenergized, it cannot again be energized unless relay Eis energized at the same time that relay T is deener'gized. That is tosay, relay M cannot become energized until a car bridges the insulatedjoints 2 betweensections Y' -U and UV. RelayM is providedwith the-usualstick circuits, one of which includes its own contact 7 and frontcontactlil of track relay T and an other of which includes contact .I las well as back contacts l2 and I3 of the signal relays H and Hrespectively. These stick .circuitsfform no part 'of my presentinvention. Relay M will also usually be provided with other pick-upcircuits to permit emergency operation otthis relay, but these circuits,likewise, constitute no part of my present invention. h V V g r Assumingthat one of the signals S1 or S has been cleared to permit a. trainmoving toward the right to enter section UV, then when such train entersthe approach section W-Y, it will open one of the stickcircuits forrelay M at contact ill of track relay T The other stick circuit will ofcourse be open at contact I2 or l3, and so relay M will becomedeenergized. Then when the train bridges the insulated joints atpointlU, relay E will be energized and relay T will be deenergized, sothat the pick-up circuit for relay M willbe closed, and this relay willbecome energized to release the approach locking forthe switch B. h

One important feature of my invention lies in the fact that momentaryinterruption of the supply of trackcircuit current for the main sectionUV cannot result in false'energization of relay M, as may be the casewhenthe-pick-up circuit for this relay is controlledonly byaback'contact of the track relay for such section. V In order to checkthe operation of the relay E, a back contact I of this relayjmay beincluded in the operating circuits for signals S and S1,,

Although I have herein shown and described only one form of apparatusembodying my in vention, it is. understoodthat various changes andmodifications may be made therein within the scope of the appendedclaims without departing from the spirit and scope ofmy invention.

Having thus described my invention, what I claim is:

1. In combination, a section of railway track containing a switch, anapproach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an auxiliary relay and asource of current connected in series across an insulated joint at oneend of said section, and a pick-up circuit for said approach lockingrelay including in series a back contact of said track relay and a frontcontact of said auxiliary relay.

2. In combination, a section of railway track containing a switch, anapproach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an auxiliary relay and asource of current connected in series across an insulated joint at oneend of said section, a signal governing traffic through said switch andcontrolled in part by a back contact of said auxiliary relay, and apick-up circuit for said approach locking relay including in series aback contact of 'said track relay and a front contact of said auxiliaryrelay.

3. In combination, a section of railway track containing a switch, anapproach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an auxiliary relay and asource of current connected in series across an insulated joint at oneend of said section, a stick circuit for said approach locking relaycontrolled in part by a train approaching said section, and a pick-upcircuit for said approach locking relay including in series a backcontact of said track relay and a front contact of said auxiliary relay.

4. In combination, a main section of railway track containing a switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an approach track sectionseparated from said main section by an intervening section and providedwith a track circuit including a track relay, said intervening sectionbeing so short that no car can occupy it without opening the track relayof either the main or the approach section, an auxiliary relay and asource of current connected in series around an insulated jointseparating said main section from said intervening section, a pick-upcircuit for said approach locking relay including in series a frontcontact of said auxiliary relay and a back contact of the track relayfor the main section, and a stick circuit for said approach lockingrelay including a front contact of the track relay for said approachsection.

5. In combination, a main section of railway track containing a switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an approach track sectionseparated from said main section by an intervening section and providedwitha track circuit including a track relay, said intervening sectionbeing so short that no car can occupy it without opening the track relayof either the main or the approach section, an auxiliary relay and asource of current connected in series around an insulated jointseparating said main section from said intervening section, a signalgoverning traific through said switch and controlled in part by a backcontact of said auxiliary relay, a pick-up circuitfor said appoachlocking relay including in series a front contact of said auxiliaryrelay anda back contact of the track relay for the main section, and astick circuit for said approach locking relay including a front contactof the track relay for said approach section.

6. In combination, a section of railway track containing a switch, anapproach locking relay, means for preventing operation of said switchunless said relay. is energized, a track circuit including a track relayconnected across the rails of said section, a normally deenergizedauxiliary relay arranged to be momentarily energized by a train enteringsaid track section, and a pickup circuit for said approach locking relayincluding in series a back contact of said track relay and a frontcontact of said auxiliary relay.

'7. In combination, a main section of railway track containing a switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, an approach track sectionextending from said main section and provided with a track circuitincluding a track relay, a normally deenergized auxiliary relay arrangedto be momentarily energized by a trainpassing from said approach sectionto said main section, a pick-up circuit for said approach locking relayincluding in series a front contact of said auxiliary relay and a backcontact of the track relay for the main section, and a stick circuit forsaid approach locking relay including a front contact of the track relayfor said approach section.

8. In combination, a stretch of railway track including a switch and aninsulated joint, a relay and a source of current connected in seriesacross said insulated joint, a stick relay having a pick-up and a stickcircuit one of which is controlled by said first relay and. the other ofwhich is controlled by other means, and means controlled by said'stickrelay for controlling said switch.

9. In combination, a stretch of railway track including a switch, anormally open track circuit including a portion of the rails of saidstretch, a source of current and a relay adapted to be energized as atrain traverses said stretch of railway, locking means controlled bytraflic conditions for at times preventing the operation of said switch,and means effective when the relay of said track circuit is energizedfor putting said locking means into condition to permit the operation ofsaid switch.

10. In combination, a stretch of railway track including a switch, anormally open track circuit for said stretch including a source ofcurrent and a relay connected around an insulated rail joint, lockingmeans controlled by traific conditions for at times preventing theoperation of said switch, and means effective when the relay of saidtrack circuit is energized for putting said locking means into conditionto permit operation of said switch.

11. In combination, a stretch of railway track including a switch, anapproach locking relay, means for preventing operation of said switchunless said relay is energized, a normally open track circuit having arelay and a current source and including a portion of the track of saidstretch which circuit is adapted to energize its relay in response to atrain traversing said stretch, a stick circuit for said approach lockingrelay controlled in part by a train approaching the stretch, and apick-up circuit for said approach locking relay including a frontcontact of the relay for said track circuit.

12; In combination, a section of railway track including a track switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, auxiliary means fordetecting the entrance of a train into said section independently of thecondition of said track circuit, and a pickup circuit for said approachlooking relay closed only when said track relay is deenergized and saidauxiliary means indicates that a train is entering said section.

13. In combination, a section of railway track including a track switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, auxiliary means fordetecting the presence of a train at a particular point adjacent saidswitch, and a pickup circuit for said approach locking relay closed onlywhen said track relay is deenergized and said auxiliary means indicatesthe presence of a train at said point.

14. In combination, a section of railway track including a track switch,an approach locking relay, means for preventing operation or" saidswitch unless said relay is energized, a track circuit including a trackrelay connected across the rails of said section, auxiliary meansindependent of said track circuit and including a normally open contactclosed only when a train enters said section, and a pickup circuit forsaid approach locking relay including in series said normally opencontact and a back contact of said track relay.

15. In combination, a section of railway track including a track switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, auxiliary means including anormally open contact closed only when a train is present at aparticular point adjacent said switch, and a pickup circuit for saidapproach locking relay including in series said normally open contactand a back contact of said track relay.

16. In combination, a section of railway track including a track switch,an approach locking relay, means for preventing operation of said switchunless said relay is energized, a track circuit including a track relayconnected across the rails of said section, auxiliary means including anormally open contact closed only when a train is present at aparticular point adjacent said switch, and a checking contact closedonly when said first mentioned contact is open, a pickup circuit forsaid approach locking relay including in series said normally opencontact and a back contact of said track relay, and means for indicatingwhen said first mentioned contact is open comprising a normally closedcircuit including said checking contact.

17. In combination, a section of railway track including a track switch,an approach locking stick relay, means for preventing operation of saidswitch unless said relay is energized, a signal for governing themovement of traffic over said switch, a track circuit including a trackrelay connected across the 1rails of said section, auxiliary meansindependent of said track circuit and including a "normally open contactclosed only when a trainis present at 'a particular point adjacent saidswitch, a pickup circuit for'said approach locking' relay closed onlywhen said contact is closed and said track relay is deenergized, and astick circuit for said approach locking relay including its own. front,-contact and a contact closed only when said signal is in its mostrestrictive condition- 18. In combination, a section of railway trackincluding a track switch, a signal for governing the movement of trafiicinto said section,ap-

proach locking means for preventing operation of the switch provided thesignal has: been cleared and a train is approaching within a pre-;determined distance of the switch, a track circuit including a trackrelay deenergized when a train enters said section, auxiliary meansindependent of said'track circuit for detecting the entrance of a traininto saidsection, and means 'for releasing said locking efiective onlywhen.

said track relay and said auxiliary means both 7 indicate that the trainhas passed the signal and has entered said section.

19. In combination, a section of railway track,

a track switch in said section, a switch machine for operating saidswitch, a stick relay which must be energized to permit control of saidswitch ,machine, a track circuit extending the entire length of saidsection and including a track relay, a track device in said section butseparate from said track circuitto 'manifest the presence of a train insaid section, and a pickup circuit for said stick relay including inseries including in series a normally open contact of said track deviceand a back contact of said track relay, and a stick circuit for saidstick relay controlled by said signal control means.

21. In a control system for railroads, a track switch, signalsgoverningtraffic over said track switch, lockingmeans normally eiIective toprevent operation of said track switch after said signals are caused toindicate stop, a detector section having a track relay, a track devicein said detector section but separate from said track circuit toindicate the presence of 'a train in said section, and means causingsaid locking means to be inefiective to prevent operation of saidtrack'switch if both said track relay and said track device indicate thepresence of a train. 7

JOHN M. PE'LIKAN.

